1. Field of the Invention
The present technology relates to a semiconductor apparatus including a plurality of element parts.
2. Description of the Related Art
In a photoelectric conversion apparatus such as a complementary metal-oxide semiconductor (CMOS) image sensor which is a type of semiconductor apparatus, a photoelectric conversion unit having a plurality of photoelectric conversion elements and a signal processing unit that processes an electric signal from the photoelectric conversion unit are built onto a single semiconductor substrate in a monolithic manner. A structure is being studied in which the photoelectric conversion unit and the signal processing unit are formed on individual parts (chips), the parts are stacked on each other, and the parts are electrically connected with each other through a conductive member. Accordingly, an occupied area (a footprint) of the photoelectric conversion apparatus in electronic equipment on which the photoelectric conversion apparatus is mounted can be efficiently utilized. The conductive member is provided to obtain the electrical connection between the parts. Such a structure may be applied to any of various semiconductor apparatuses that realize so-called system-in packages.
Japanese Patent Laid-Open No. 2011-096851 describes that inter-substrate wiring (68) is provided as the conductive member for obtaining the electrical connection between semiconductor substrates (31, 45) corresponding to the parts.
If the inter-substrate wiring in Japanese Patent Laid-Open No. 2011-096851 is formed of copper, the copper contained in the inter-substrate wiring may be diffused to a semiconductor well region (32) surrounding the inter-substrate wiring or an interlayer insulating film (39). Consequently, the semiconductor apparatus may not be correctly operated, or a desirable performance may not be obtained due to contamination with the copper. Sufficient reliability may not be obtained. This technique provides a semiconductor apparatus having high reliability.